Siemens SIMATIC S7-300 FM 350-1 - Page 105

Operating Modes, parameters and commands
7.3 Count modes
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
105
Edge-triggered opening and closing of the HW gate
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


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&RXQWSXOVHV
',6WDUW
',6WRS
2SHQJDWH
&ORVHJDWH
&RXQWHUVWDWXV
Figure 7-11 Edge-triggered opening and closing of the HW gate
The edge-triggered HW gate is opened by setting a positive edge at digital input DI-Start. It
is closed again by setting a positive edge at digital input DI-Stop.
If a positive edges is set in parallel at both inputs, an open gate will be closed, whereas a
closed gate remains closed. When digital input DI-Stop is set, a positive edge at digital input
DI-Start can not open the gate.
Status at the inputs DI-Start and DI-Stop
The status at inputs DI-Start and DI-Stop is returned at the green LEDs I0 and I1, and in the
user program at the STS_STA and STS_STP bits in the DB of FC CNT_CTL1.
Gate status
The gate status is indicated by the STS_GATE bit in the user program.
Opening and closing the SW gate
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
6:B*$7(
%LWUHVHW
&RXQWHUVWDWXV
&RXQWSXOVHV
%LWVHW
Figure 7-12 Opening and closing the software gate
You open /close the SW gate by setting / resetting input parameter SW_GATE at
FC CNT_CTL1.
You can retrigger the closed gate by setting input parameter SW_GATE once again.
Edge-triggered opening and closing of the SW gate is not supported.